Green vat-dye and process of making same.



i To all whom it may concern:

ATES

PATET @FFICE,

GADIENT ENGI, OF BASEL, SWITZERLAND, ASSIGNOR TO FIRM OF SOCIETY OF OHEMTPAL INDUSTRY IN BASLE, Ob BASEL, SWITZERLAND.

GREEN VAT-DYE AND PROCESS OF MAKING SAME.

Be it known that I,' GADIENT Eu er, a

chemist and doctor of philosophy, a citizen of the Swiss Republic, and resident of Basel, Switzerland, have invented newand useful Green 'Vat-Dyestuffsand a Process for the Manufacture ot the Same, .of which the folrids, with suitable reducing a ents.

lowing is a full, clear, and exact specification. It 'is knownthat the dyestul'f designed beta-naphthdndiqo and corresponding with the constitutiona formula:

coco l I l l l' l \gv dyes cotton without a mordant in an alkaline Vat green" tints. On account. of the want of fastness of these tintsto washin and i 7, their phgor degree of fastness to chlorin, betana ht 2 0.

into the molecule. This chan e can, for exampleinbe effected by first sii jecting betathisatin thus obtained, preferably after transforming them into corresponding chlo- There are thus obtained halogen su stitution' derivatives of beta-naphthindigo which constitute products of very greatvalue, since they, dye cotton without a mordan t in an al kallne vat vivid green tints of excellent fastness to washing and 00d fastness to chlorin. The invention Wil be illustrated by the following examples:

Example I. 10 parts of beta naphthisatin, 50 -p'arts of glacial acetic acid and 3033 parts of bromin are heated to boiling for about 1%2 hours in a reflux apparatus in an oil bath, during which operation much hydrogen. bromid is evolved. After cooling, the brominated derivative separates, wit excellent yield, in the form of small redbrown crystals which are isolated by filtra- Patented Nov. 26, 1907.

tion, wash ed with glacial acetic acid and dried. To transform this product into? a bromo-derivativeof beta-naphthindi o, the

procedure is as follows: 10 parts of the romo-' naphthisatin are well mixed with 100 parts of phosphorus oxychlorid and 6 parts of phosphorus pentachlorid, and the whole is heated to boiling in a reflux apparatus in anoil bath for 40 minutes. After cooling, and if neces sary after the excess of phosphorus oxychlorid has been expelled by distillation, the mass is oured into aboutfiOO parts of a solution of l the lydroiodic acid amounting to 10 per cent of the solution; the whole is boiled for a short time, cooled and then poured into'an a ueous.

solution of sulfurous acid, thus producing an abundant precipitate of smallclear grayish yellow crystals'i' The mixture is now made alkaline with diluted caustic soda and air is blown through the mass,'-'the latter being hot, for a short time, whereupon the dyestuif is precipitated in the form of reen flocks which are filtered, washed and dried.

The bromonaphthindigo thus obtained forms a dark green crystalline powder, soluble in concentrated sulfuric acid to a blue solution tending slightly towards green, little soluble in cold nitrobenzene to a green solution and easily soluble in hot nitrobenzene to a greenish blue solution. By treatment with alkaline reducin agents, a red-brown liquid iydroiodic acid in glacial acetic acid,

is obtained Whic dyes cotton in a vat, green tints distinguished from those obtained with beta-naphthindigo by an excellent fastness to washing, a better fastness to chlorin and a greater tinctorial richness.

Example 11. 1 part of brom-beta-naphthisatin is transformed according to the indications of Example I into the corresponding bromonaphthisatinchlorid and after cooling the said chlorid 'separated in the form of small, clear-brown crystals,.is isolated by filtration and drying. Then this bromonaphthisatin chlorid is boiled, with a mixture of 10 arts of a concentrated aqueous solution of ammoniumhydrosulfid and 10 parts of alcohol in a reflux apparatus, during about 2 hours; hereafter the quadru 1e 01' quin tuple quantity of water is adde to the mass and the resulting mixture boiled again for about 1 hour, whereby the bromo-betanaphthindigo separates as .a heavy green, crystalline powder, which is isolated by filtration, washing and drying.

What. I claim is: 1: The described process for the manufacture of halogen derivatives of beta-naphthindigo, which process consists in first treating beta-naphthylisatin with halogenating' agentsgthen reducing the resulting halo en derivatives of beta-naphthylisatin, pre erably after their conversion .into the corresponding chlorids, and finally treating the so obtained reduction products with suitable oxidizing agents.

2. The described process for the lnanufac- 37, As new products, the halogen derivatives of beta-naphthylindigo, which can be obtained by first treating beta-na hthylisatin with halogenating agents, t en re- (lifting the resulting halogen derivatives of beta-naphthylisatin after their conversion into the corresponding chlorids and finally treating the 'so obtained reduction products with suitable oxidizing agents, the said halogen derivatives of beta-naphthylindigo being vat-dyestuffs dyeing unmordanted cotton from alkaline vats green tints fast to washing, light and chlorin.

4. As a new article of manufacture the de-.

scribed green vat-dyestuff, being a brornoderivative of beta-naphthylindigoand constituting, in dry state, a dark-greencrystalline powder dissolving in concentrated sul furic acid with reenish blue color, only difli-' cultly soluble in cold nitrobenzene with a green color, easily soluble in hot nitrobenzene with a greenish-blue color and yielding by treatment with alkaline reducing agents, a

reddish-brown vat, from which unmordanted cotton is-dyed 'in vivid green shades, fast to washing, light and chlorin.

In wltness whereof I have hereunto signed my name this 4 day of June 1907, in the presence of two subscribing witnesses.

, GADIENT EN GI.

Witnesses:

GEO. GIEFORD, AMAN I. BITTER. 

